Twitch and M-wave potentiation induced by intermittent maximal voluntary quadriceps contractions: differences between direct quadriceps and femoral nerve stimulation

Introduction: The aim of this study was to investi-gate differences in twitch and M-wave potentiation in the quadri-ceps femoris when electrical stimulation is applied over thequadriceps muscle belly versus the femoral nerve trunk. Meth-ods: M-waves and mechanical twitches were evoked usingdirect qu...

Descripción completa

Detalles Bibliográficos
Autores: Rodríguez Falces, Javier, Maffiuletti, Nicola A., Place, Nicolas
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2013
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/55591
Acceso en línea:https://hdl.handle.net/2454/55591
Access Level:acceso abierto
Palabra clave:M-wave potentiation
Twitch potentiation
Neuromuscular electrical stimulation
Over-the-muscle stimulation
Femoral nerve stimulation
Direct quadriceps stimulation
Descripción
Sumario:Introduction: The aim of this study was to investi-gate differences in twitch and M-wave potentiation in the quadri-ceps femoris when electrical stimulation is applied over thequadriceps muscle belly versus the femoral nerve trunk. Meth-ods: M-waves and mechanical twitches were evoked usingdirect quadriceps muscle and femoral nerve stimulationbetween 48 successive isometric maximal voluntary contrac-tions (MVC) from 10 young, healthy subjects. Potentiation wasinvestigated by analyzing the changes in M-wave amplituderecorded from the vastus medialis (VM) and vastus lateralis(VL) muscles and in quadriceps peak twitch force. Results:Potentiation of twitch, VM M-wave, and VL M-wave weregreater for femoral nerve than for direct quadriceps stimulation(P < 0.05). Despite a 50% decrease in MVC force, the ampli-tude of the M-waves increased significantly during exercise.Conclusions: In addition to enhanced electrogenic Na1-K1pumping, other factors (such as synchronization in activation ofmuscle fibers and muscle architectural properties) may signifi-cantly influence the magnitude of M-wave enlargement.